Some problems in shock reflection and diffraction

The possible shock reflection patterns in steady and unsteady flow are described in detail, and conditions which have been calculated from the Rankine-Hugoniot relations are stated for their existence. There are experimental results which show reflection patterns in unsteady flow which are forbidden by these conditions. It is suggested that a discrepancy between theory and experiment may be explained in terms of viscous effects. To confirm this a theoretical investigation is made for weak shocks and it is found that viscous effects are important both in the boundary layer on the surface from which the reflection takes place, and in the immediate neighbourhood of the triple point in a Mach reflection